Recently discovered plasmids that replicate in Bacillus subtilis have been shown to be useful as molecular cloning vehicles. This proposal concerns the utilization of these vehicles for cloning of the genes for sporulation. The focal point of this research is the development of the genetics of sporulation with particular emphasis on those genes that function from stage II of sporulation to the termination of the process. The presently known sporulation loci will be cloned in an active form. The products of these loci will be identified in special strains where the plasmids bearing them can be amplified to high copy number. Some of these gene products will be purified for further study. A detailed genetic and physical map of a region of sporulation genes for several stages of sporulation will be prepared by in vitro mutagenesis, complementation and physical methods. A procedure will be developed to determine the direction of transcription of fine structure genetic mapped genes. The cloned genes and their genetic map will be probes to determine the molecular mechanisms controlling developmental gene expression.